Contents

Proposal

This was already discussed with no results. I propose to introduce default layer value for bridge=yes and tunnel=yes. Those will be layer=1 and layer=-1 respectively. All other elements will stay as is, i.e. with layer=0 by default.

Some of the objects which are tagged with tunnel=yes contain incorrect tags, for example, layer=.1, layer=.-1, layer=/1, layer=1-, layer=-1#, layer=layer

The mentioned statistics shows that tag layer=* is often omitted for bridges and tunnels. There is a chance that it is not set even for the bridges and tunnels that cross other ways. This leads to uncertainty and with current approach without default layer value often indicates an error in mapping. See #Examples.

Why should we put efforts in defining facts which are obvious in majority of cases? And when there is an exception it could always be clarified. Bridge with layer=1 is just like water=yes + color=colorless. Of course, water could be white, red, and of many other colors. But the vast majority of water is colorless, and who would care to search some colorless water? If you're searching for a white water, you say: find me some white water. Same rationale makes it redundant to specify that a bridge is above the ground and tunnel is under the ground.

Specifying layer=1 and layer=-1 respectively for bridge=yes and tunnel=yes increases the amount of data that leads to redundancy.

I approve this proposal. -- There is an important rule for API builders: if some value is used in majority of cases, it should be set as default value. This proporsal follows it --Osmisto 11:21, 19 January 2011 (UTC)

I oppose this proposal. For more than 2 years, the documentation of key layer says that objects without a layer tag is assumed to be on layer 0. I also believe that this change will make the tagging standards more complex. -- Nic 16:45, 19 January 2011 (UTC)

I approve this proposal. Renderers already assume this (or maybe ±½) for good reason. Let's adjust rules to usage. And honestly, I like to be lazy. --Fkv 08:32, 20 January 2011 (UTC)

I oppose this proposal. Believing one could change defaults only by "voting" on the wiki is totally backwards to the way the whole project has been evelving and only leads to broken data/assumptions. Just look at what happened with highway=path. Alv 11:13, 22 January 2011 (UTC)

I oppose this proposal. -- The API should not modify the users data at all, renderers should be free to render bridges as they like, and editors should add a feature to make tagging of this easy if they like to. Basically – fix JOSM, rather than breaking the API to cancel problems out. Beelsebob 12:26, 23 January 2011 (UTC)

I have comments but abstain from voting on this proposal. -- I am unsure what this proposal is about. If it is about defining that "whenever a renderer encounters a bridge without a layer attribute, it should assume layer=1" then this is for the renderer to decide and not for us (or, if you like, for the editor to set an extra layer=* if none is given). This Wiki has no authority to define what renderers or editors should do. If this proposal is about an automated edit in which all bridges/tunnels would receive a layer tag where there is none yet (or about an automated edit where bridges with layer=1 would lose that tag because it is now considered default), then I would certainly revert that edit. --Frederik Ramm 16:54, 23 January 2011 (UTC)